Wall scanner

ABSTRACT

Embodiments of the invention relate to a wall scanner that includes a housing, a plurality of sensors, a display, and a control section. The housing includes a handle portion and a body portion. The handle portion is adapted to receive a removable and rechargeable battery pack such as a high-voltage lithium-ion (“Li-Ion”) battery pack. The body portion of the housing encloses the plurality of sensing devices, such as, for example, capacitive plate sensors for sensing the presence of a stud behind a surface, a D-coil sensor for identifying the presence of metal behind the surface, and a non-contact voltage sensor for detecting the presence of live wires carrying AC currents. The display is configured to display, among other things, the location of an object behind the surface in real-time, the depth of an object behind the surface, and whether an object behind the surface is ferrous or non-ferrous. The control section includes a plurality of actuation devices for controlling the functions and operations of the wall scanner, such as the scanning mode.

RELATED APPLICATIONS

This application is a continuation-in-part of prior filed co-pendingU.S. patent application Ser. No. 12/399,835, filed Mar. 6, 2009, theentire contents of which are hereby incorporated by reference.

BACKGROUND

Embodiments of the invention relate to wall sensors. Wall sensorsinclude the capability of detecting, for example, wooden or metal studshidden behind a surface. In some instances, wall sensors include one ormore plate sensors or high frequency transmitters for determiningwhether an object is hidden behind a surface. Wall sensors also includean indicating device or multiple indicating devices for alerting a userto the presence of an object that is hidden behind a surface. Indicatingdevices can include visual indicators such as light emitting diodes(“LEDs”), audible indicators such as a small speaker, or a combinationthereof.

SUMMARY

Embodiments of the invention include a wall sensor or wall scanner thatis capable of providing a plurality of wall scanning technologies and ahigh-resolution display in a single hand-held device. Embodiments alsoinclude a wall scanner that is ergonomically designed to provide acomfortable and easy-to-grip handle portion, a control sectionaccessible with a single hand while that hand grips the handle portion,and a display that is not obstructed by a user's hand during normaloperation of the wall scanner.

In one embodiment, the invention provides a wall scanner that includes ahousing, a plurality of sensors, a display, a control section, and aplurality of wheels. The housing includes a handle portion and a bodyportion. The handle portion is adapted to receive a high-voltageremovable and rechargeable battery pack, such as a lithium-ion(“Li-Ion”) battery pack (e.g., a 12V Li-Ion battery pack). The bodyportion of the housing encloses the plurality of sensors, such as, forexample, capacitive plate sensors for sensing the presence of a studbehind a surface, a D-coil sensor for identifying the presence of metalbehind the surface, and a non-contact voltage sensor for detecting thepresence of live wires carrying AC currents behind the surface. Thedisplay is, for example, a negative LCD (“NLCD”), and is configured todisplay a plurality of status indications related to the operation ofthe wall scanner. For example, the display can display, among otherthings, the operational mode of the wall scanner, the location of anobject behind the surface in real-time, the depth of an object behindthe surface, and whether an object behind the surface is ferrous ornon-ferrous. The control section includes a plurality of actuationdevices for controlling the functions and operations of the wallscanner, such as the scanning mode. The plurality of wheels allow thewall scanner to roll along the surface in a linear manner.

In one embodiment, the invention provides a wall scanner for sensingobjects behind a surface. The wall scanner includes a housing having abody portion and a handle portion, a first sensor, a second sensor, anda non-contact voltage sensor. The handle portion forms a first axis andincludes a first recess. The first recess is operable to receive aremovable battery pack along the first axis. The first sensor is of afirst sensor type and senses a first object of a first object typebehind the surface. The second sensor is of a second sensor type andsenses a second object of a second object type behind the surface. Thefirst sensor type is different than the second sensor type, and thefirst object type is different than the second object type. Thenon-contact voltage sensor is operable to detect a medium carrying analternating current behind the surface, and the display is configured todisplay a plurality of indications to a user. The indications include atleast an indication of a depth of the second object behind the surfaceand a graphical representation of the location of the first objectbehind the surface.

In another embodiment, the invention provides a method for operating awall scanner that includes a handle portion. The method includesinserting a removable battery pack into a receiving chamber of thehandle portion, sensing a first object of a first object type behind asurface using a first sensor of a first sensor type, and sensing asecond object of a second object type behind the surface using a secondsensor of a second sensor type. The first sensor type is different thanthe second sensor type, and the first object type is different than thesecond object type. The method also includes detecting, using anon-contact voltage sensor, a medium carrying an alternating currentbehind the surface, and displaying, on a display, a plurality ofindications to a user. The indications include at least an indication ofa depth of the second object behind the surface and a graphicalrepresentation of the location of the first object behind the surface.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a perspective view of a wall scanner according anembodiment of the invention.

FIG. 2 illustrates a top view of the wall scanner of FIG. 1.

FIG. 3 illustrates a front view of the wall scanner of FIG. 1.

FIG. 4 illustrates a side view of the wall scanner of FIG. 1.

FIG. 5 illustrates an exploded view of the wall scanner of FIG. 1.

FIG. 6 illustrates an exploded view of a lower portion of the wallscanner of FIG. 1.

FIG. 7 illustrates an exploded view of a side portion of the wallscanner of FIG. 1.

FIG. 8 illustrates an exploded view of a control section and a displayaccording to an embodiment of the invention.

FIG. 9 is a perspective view of a battery pack.

FIG. 10 is an exploded view of the battery pack of FIG. 9.

FIG. 11 is a top view of the battery pack of FIG. 9.

FIG. 12 is a block diagram of a wall scanner according to an embodimentof the invention.

FIG. 13 illustrates a control section of a wall scanner according to anembodiment of the invention.

FIG. 14 illustrates a plurality of display screens of a wall scanneraccording to an embodiment of the invention.

FIG. 15 illustrates a plurality of display screens of a wall scanner ina stud scanning mode according to an embodiment of the invention.

FIG. 16 illustrates a plurality of display screens of a wall scanner ina metal scanning mode according to an embodiment of the invention.

FIG. 17 illustrates a control process for a wall scanner according to anembodiment of the invention.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless specified or limited otherwise, theterms “mounted,” “connected,” “supported,” and “coupled” and variationsthereof are used broadly and encompass both direct and indirectmountings, connections, supports, and couplings. Further, “connected”and “coupled” are not restricted to physical or mechanical connectionsor couplings.

Various embodiments herein describe a wall scanner that is capable ofdetecting a plurality of objects hidden behind a plurality of differentsurfaces. The wall scanner includes a housing, a plurality of sensors, adisplay, a control section, and a plurality of wheels. The housingincludes a handle portion and a body portion. The handle portionincludes a recess that is adapted to receive a high-voltage removableand rechargeable battery pack.

As a result of receiving operational power from the high-voltageremovable and rechargeable battery pack, the wall scanner is capable ofincluding a variety of additional features or functions that demandincreased power. For example, the wall scanner can include ahigh-intensity LED flashlight, a backlighted control section oractuators, a high-resolution LCD, a color LCD, and/or an additional orremote display. Conventionally powered wall scanners (e.g., wallscanners powered by alkaline batteries) are unable to provide therequired voltage and current to power these additional features, or theoperational runtime (i.e., the amount of time for which the batteriescan power the wall scanner before the batteries need to be replaced orrecharged) of the alkaline batteries is shortened. In contrast, thehigh-voltage removable and rechargeable battery pack of a wall scanneraccording to embodiments of the invention is capable of powering boththe additional features of the wall scanner and the described sensingand display features, while maintaining an operational runtime that iscomparable to or longer than a conventional wall scanner that does notinclude additional features.

FIGS. 1-4 illustrate the wall scanner 5 and housing 10 according to anembodiment of the invention. A handle portion 15 of the wall scannerhousing 10 includes a battery pack recess 20 (see FIG. 5) adapted toreceive a high-voltage removable and rechargeable battery pack 25. Thebattery pack recess 20 includes a plurality of terminals (shown as 145in FIG. 7) for electrically connecting the battery pack 25 to the wallscanner 5. Additionally, the handle portion 15 includes a plurality ofrecessed gripping portions 35 that provide additional grip to a user.

The handle portion 15 and the battery pack 25 define a first axis 41 ofthe wall scanner 5. The handle portion 15 is coupled to and extends fromthe body portion 40 of the wall scanner 5 such that a recess 45 isformed between the body portion 40 and the handle portion 15. Theextension of the handle portion 15 from the body portion 40 allows thewall scanner 5 to receive the battery pack 25. In some embodiments, therecess 45 between the handle portion 15 and the body portion 40 isclosed by first and second connecting portions 50 and 55. In otherembodiments, the recess 45 is open and includes a single connectingportion. The recess 45 defines a space for accommodating the fingers ofa user while the user is holding the wall scanner 5.

The handle portion 15 extends approximately half the length of thehousing 10 and is approximately parallel to the body portion 40 and adisplay 60. In one embodiment, the first axis 41 is parallel to a secondaxis 43 which extends through a center of the body portion 40. In otherembodiments, the first axis 41 is not parallel to the second axis 43,and the first axis 41 intersects the second axis 43 at a point adistance, d, away from the wall scanner 5. The display 60 is positionedon the body portion 40 such that the display 60 is not blocked by theuser's hand when the wall scanner 5 is being gripped. The controlsection 65 is provided on the first connecting portion 50 between thebody portion 40 and the handle portion 15 of the wall scanner 5. Thecontrol section 65 is positioned at an oblique angle with respect to thebody portion 40 of the housing such that the buttons or switches(described below) within the control section 65 can be activated by theuser using the same hand with which the user is gripping the wallscanner 5. In some embodiments, the wall scanner 5 also includes one ormore LEDs for providing an indication to the user of the status of thewall scanner 5, the battery pack 25, or both. The wheels 70 arerotatably coupled to the housing 10 to facilitate movement of the wallscanner 5 along a surface. In the illustrated embodiment, the wheels 70are idle wheels, but may alternatively be driven wheels that are poweredby the battery pack 25.

FIG. 5 illustrates an exploded view of the wall scanner 5 shown in FIGS.1-4. The wall scanner 5 includes a base housing assembly 100, right andleft housing assemblies 105 and 110, a panel assembly 115, and thebattery pack 25. An exploded view of the base housing assembly 100 isshown in FIG. 6. The base housing assembly 100 includes a main printedcircuit board assembly (“PCB”) 120, a sensor board 125 which includesplate sensors for sensing studs, a D-coil sensor 130 for sensing metal,a base 135, and the wheels 70. An exploded view of the right housingassembly 105 is shown in FIG. 7. The left housing assembly 110 issimilar to the right housing assembly 105 and is not described indetail. The right housing assembly 105 includes contact plate terminals145, a battery contact PCB 150, a right half of the housing 155, anindicator lens 160, and an LED 165. An exploded view of the panelassembly 115 is shown in FIG. 8. The panel assembly 115 includes akeypad 170, a key holder 175, a rubber key 180, a light guide 185, a keyPCB 190, a key panel 195, an LCD lens 200, and an LCD assembly 205.

FIGS. 9, 10, and 11 illustrate the battery pack 25 for use with the wallscanner 5. In the illustrated embodiment, the battery pack 25 includesbattery cells having a lithium-based chemistry such that the batterypack 25 is over 65% lighter and 50% smaller than an equivalentnickel-cadmium (“NiCd”) battery pack. The lithium-ion battery pack 25also provides a longer operational run-time for the wall scanner 5, anda longer life (e.g., number of recharge cycles) than other non-lithiumbased battery packs.

The illustrated battery pack 25 includes a casing 300, an outer housing305 coupled to the casing 300, and a plurality of battery cells 310(shown in FIG. 10) positioned within the casing 300. The casing 300 isshaped and sized to fit within the recess 20 in the wall scanner 5 toconnect the battery pack 25 to the wall scanner 5. The casing 300includes an end cap 315 to substantially enclose the battery cells 310within the casing 300. The illustrated end cap 315 includes two powerterminals 320 configured to mate with corresponding power terminals 145of the wall scanner 5. In other embodiments, the end cap 315 may includeterminals that extend from the battery pack 25 and are configured to bereceived in receptacles supported by the wall scanner 5. The end cap 315also includes sense or communication terminals 325 (shown in FIG. 11)that are configured to mate with corresponding terminals of the wallscanner 5. The terminals 325 couple to a battery circuit (not shown).The battery circuit can be configured to monitor various aspects of thebattery pack 25, such as pack temperature, pack and/or cell state ofcharge, etc. and can also be configured to send and/or receiveinformation and/or commands to and/or from the wall scanner. In oneembodiment, the battery circuit operates as illustrated and described inU.S. Pat. No. 7,157,882 entitled “METHOD AND SYSTEM FOR BATTERYPROTECTION EMPLOYING A SELECTIVELY-ACTUATED SWITCH,” issued Jan. 2,2007, the entire contents of which are hereby incorporated by reference.In another embodiment, the battery circuit operates as illustrated anddescribed in U.S. Patent Publication No. 2006/0091858 entitled “METHODAND SYSTEM FOR BATTERY PROTECTION,” filed May 24, 2005, the entirecontents of which are also hereby incorporated by reference.

The casing 300 and power terminals 320 substantially enclose and coverthe terminals 145 of the wall scanner 5 when the pack 25 is positionedin the recess 20. That is, the battery pack 25 functions as a cover forthe recess 20 and terminals 145 of the wall scanner 5. Once the batterypack 25 is disconnected from the wall scanner 5 and the casing isremoved from the recess 20, the battery terminals 145 on the wallscanner are generally exposed to the surrounding environment.

The outer housing 305 is coupled to an end of the casing substantiallyopposite the end cap 315 and surrounds a portion of the casing 300. Inthe illustrated construction, when the casing 300 is inserted into orpositioned within the corresponding recess 20 in the wall scanner 5, theouter housing 305 generally aligns with an outer surface of the wallscanner 5. In this construction, the outer housing 305 is designed tosubstantially follow the contours of the wall scanner 5 to match thegeneral shape of the housing 10. In such embodiments, the outer housing305 generally increases (e.g., extends) the length of the handle portion15 of the wall scanner 5.

In the illustrated embodiment, two actuators 330 (only one of which isshown) and two tabs 335 are formed in the outer housing 305 of thebattery pack 25. The actuators 300 and the tabs 335 define a couplingmechanism for releasably securing the battery pack 25 to the wallscanner 5. Each tab 335 engages a corresponding recess formed in thewall scanner 5 to secure the battery pack 25 in place. The tabs 335 arenormally biased away from the casing 300 (i.e., away from each other)due to the resiliency of the material forming the outer housing 305.Actuating (e.g., depressing) the actuators 330 moves the tabs 335 towardthe casing 300 (i.e., toward each other) and out of engagement with therecesses such that the battery pack 25 may be pulled out of the recess20 and away from the wall scanner 5. Such an arrangement allows a userto quickly remove the battery pack 25 from the wall scanner 5 forrecharging or replacement without the use of tools. In otherembodiments, the battery pack 25 may include other suitable couplingmechanisms to releasably secure the battery pack 25 to the wall scanner5, as discussed below.

As shown in FIG. 10, the battery pack 25 includes three battery cells310 positioned within the casing 300 and electrically coupled to theterminals 320. The battery cells 310 provide operational power (e.g., DCpower) to the wall scanner 5. In the illustrated embodiment, the batterycells 310 are arranged in series, and each battery cell 310 has anominal voltage of approximately four-volts (“4.0V”), such that thebattery pack 25 has a nominal voltage of approximately twelve-volts(“12V”). The cells 310 also have a capacity rating of approximately 1.4Ah. In other embodiments, the battery pack 25 may include more or fewerbattery cells 310, and the cells 310 can be arranged in series,parallel, or a serial and parallel combination. For example, the pack 25can include a total of six battery cells 310 in a parallel arrangementof two sets of three series-connected cells. The series-parallelcombination of battery cells 310 creates a battery pack 25 having anominal voltage of approximately 12V and a capacity rating ofapproximately 2.8 Ah. In other embodiments, the battery cells 310 mayhave different nominal voltages, such as, for example, 3.6V, 3.8V, 4.2V,etc., and/or may have different capacity ratings, such as, for example,1.2 Ah, 1.3 Ah, 2.0 Ah, 2.4 Ah, 2.6 Ah, 3.0 Ah, etc. In otherembodiments, the battery pack 25 can have a different nominal voltage,such as, for example, 10.8V, 14.4V, etc. In the illustrated embodiment,the battery cells 310 are lithium-ion battery cells having a chemistryof, for example, lithium-cobalt (“Li—Co”), lithium-manganese (“Li—Mn”),or Li—Mn spinel. In other embodiments, the battery cells 310 may haveother suitable lithium or lithium-based chemistries.

FIG. 12 is a block diagram of a wall scanner 5 according to anembodiment of the invention. The wall scanner 5 includes a main systemmodule 400, the stud sensor 125, the D-coil sensor 130, and the display60. The main system module 400 includes, among other things, a wallscanner controller 420, a signal conditioning module 425, a peakdetection module 430, and an analog-to-digital conversion module 435.The display 60 is, for example, a 128×64 dot matrix liquid crystaldisplay (“LCD”) or negative LCD (“NLCD”). The wall scanner controller420 includes, for example, a PCB such as PCB 120 shown in FIG. 6. ThePCB 120 is populated with a plurality of electrical and electroniccomponents which provide operational control and protection to the wallscanner 5. In some embodiments, the PCB 120 includes a control orprocessing unit such as a microprocessor, a microcontroller, or thelike. In some embodiments, the controller 420 includes, for example, theprocessing unit, a memory, and a bus. The bus connects variouscomponents of the controller 420 including the memory to the processingunit. The memory includes, in many instances, read only memory (“ROM”)and random access memory (“RAM”). The controller 420 also includes aninput/output system that includes routines for transferring informationbetween components within the controller 420. Software included in theimplementation of the wall scanner 5 is stored in the ROM or RAM of thecontroller 420. The software includes, for example, firmwareapplications and other executable instructions. In other embodiments,the controller 420 can include additional, fewer, or differentcomponents.

The PCB 120 also includes, for example, a plurality of additionalpassive and active components such as resistors, capacitors, inductors,integrated circuits, and amplifiers. These components are arranged andconnected to provide a plurality of electrical functions to the PCB 120including, among other things, filtering, signal conditioning, andvoltage regulation. For descriptive purposes, the PCB 120 and theelectrical components populated on the PCB 120 are collectively referredto herein as “the controller” 420. The controller 420 receives signalsfrom the sensors within the wall scanner, conditions and processes thesignals, and transmits processed and conditioned signals to the display60. The display 60 receives the processed and conditioned signals anddisplays an indication of a sensed characteristic of an object hiddenbehind a surface. The signal conditioning module 425 provides signals toand receives signals from the stud sensor 125, as described below; thepeak detection module 430 receives signals from and sends signals to theD-coil sensor 130, as described below; and the analog-to-digitalconversion module 435 provides the conversion necessary for thecontroller 420 to interpret analog signals from the D-coil sensor 130.

In some embodiments, a battery pack controller (not shown) can provideinformation to the wall scanner controller 420 related to a battery packtemperature or voltage level. The wall scanner controller 420 and thebattery pack controller also include low voltage monitors andstate-of-charge monitors. The monitors are used by the wall scannercontroller 420 or the battery pack controller to determine whether thebattery pack 25 is experiencing a low voltage condition which mayprevent proper operation of the wall scanner 5, or if the battery pack25 is in a state-of-charge that makes the battery pack 25 susceptible tobeing damaged. If such a low voltage condition or state-of-chargeexists, the wall scanner 5 is shut down or the battery pack 25 isotherwise prevented from further discharging current to prevent thebattery pack 25 from becoming further depleted.

The wall scanner 5 is operable to detect the presence of a stud, such asa wood stud or metal joists within residential, commercial, andindustrial structures using the stud sensor 125. The wooden studs ormetal joists can be detected when hidden behind surfaces composed of,for example, plaster, non-metallic wall materials, wooden panels, wallboard, and the like. The stud sensor 125 includes a sensor circuit witha pair of sensors. Each sensor includes a coplanar primary plate 440Awith a single side coplanar plate 440B arranged between the primaryplates. The presence and location of the stud is then determined in amanner similar to that described in U.S. Patent Application PublicationNo. 2008/0238403, titled “STUD SENSOR,” the entire contents of which arehereby incorporated by reference.

The wall scanner 5 is also configured to operate in a metal scanningmode. The metal scanning mode is operable to detect both ferrous (i.e.,iron based) and non-ferrous (e.g., copper) metals within residential,commercial, and industrial structures. While in the metal scanning mode,the wall scanner 5 can detect metal (e.g., rebar, metal conduit, copperpiping, etc.) behind surfaces composed of wall board, tile, plaster,brick, or the like. The wall scanner 5 can also detect metal withinwalls composed of concrete, masonry, wood, brick, or the like. In someembodiments, the wall scanner 5 is operable to sense metal to a depthof, for example, six inches.

The D-coil sensor 130 illustrated in FIG. 6 uses an inductively coupledsensor that includes overlapping D-shaped transmitter and receiver coils445A and 445B. When the D-coil sensor 130 detects a metallic object, thesensor 130 outputs a signal to the controller 420 indicating thelocation of the object. The wall scanner 5 detects the presence of metalin a manner similar to that described in U.S. Patent ApplicationPublication No. 2008/0272761, titled “DEVICE AND METHOD OF DETECTINGFERRITE AND NON-FERRITE OBJECTS,” the entire contents of which arehereby incorporated by reference.

The wall scanner 5 is also configured to detect the presence of “live”(i.e., energized) electrical wiring behind a surface. In someembodiments, the wall scanner 5 includes an AC detection circuit such asthat described in U.S. Pat. No. 6,894,508, titled “APPARATUS AND METHODFOR LOCATING OBJECTS BEHIND A WALL LINING,” the entire contents of whichare hereby incorporated by reference. In other embodiments, the wallscanner 5 includes a detachable non-contact voltage detector (notshown), such as that described in co-pending U.S. patent applicationSer. No. 12/421,187, filed on Apr. 9, 2009 and titled “SLIDABLYATTACHABLE NON-CONTACT VOLTAGE DETECTOR,” the entire contents of whichare hereby incorporated by reference, which is slidably attachable tothe housing 10 of the wall scanner 5. The wall scanner 5 includes theLED 165 for indicating the detection of an AC voltage. The LED 165 canbe located at a first end of the wall scanner 5, such as the endopposite the battery pack 25 (as shown in FIG. 7), on the display 60, orboth. The wall scanner 5 is operable to sense the presence of ACvoltages regardless of the operational mode of the wall scanner 5 (e.g.,metal sensing mode or stud sensing mode), and the wall scanner 5 doesnot need to be calibrated to detect the presence of AC voltages.

FIG. 13 illustrates the control section 65 of the wall scanner 5. Thecontrol section 65 is positioned between the display 60 and the handleportion 15 along the first axis 41. The control section 65 includesbuttons, switches, or other actuation devices for controlling thefunction and operation of the wall scanner 5. In some embodiments, thecontrol section 65 includes a metal sensing mode button 500, a studsensing mode button 505, a menu button 510, a power button 515, and acalibration button 520. In other embodiments, the control section 65includes additional buttons or switches for controlling additional ordifferent features or functions of the wall scanner 5. One or more ofthe buttons included in the control section 65 may have multiplefunctions such as selecting an operational mode and enabling a user toscroll through menu options on the display 60. In the illustratedembodiment of the control section 65, the buttons are arranged in acircular manner. In other embodiments, the buttons in the controlsection 65 can be arranged in a variety of different configurations,such as a grid or an array. In various embodiments of the controlsection 65, the buttons are configured such that a user can access andselect each button using a single hand (e.g., the same hand the user isusing to grip the handle portion of the wall scanner).

The display 60 is symmetrically aligned along the first axis 41 definedby the handle portion 15 and the battery pack 25. The display 60 isconfigured to display a plurality of status indications related to theoperation of the wall scanner 5. For example, the display 60 candisplay, among other things, the operational mode of the wall scanner 5,the location of an object hidden behind the surface in real-time, thedepth of an object hidden behind the surface, whether an object hiddenbehind the surface is ferrous or non-ferrous, battery pack power level,and an indication of whether sound (i.e., audible indication) is turnedon or off. FIGS. 14-16 illustrate embodiments of wall scanner statusindications that the display 60 is configured to display.

The controller 420 receives signals from the sensors, processes orconditions the signals, and transmits the conditioned signals to thedisplay 60, as described above. The display 60 receives the conditionedsignals and displays an image, a value (e.g., a distance, coordinates,etc.), an alert relating to the detected object, test results,measurement values, properties of the wall scanner, etc. The display 60includes lighted symbols, such as white alphanumeric symbols, on a blackbackground. The display 60 improves the visibility of the display in lowor poor lighting conditions, such as outdoor, dark, or dirty conditions.Additionally or alternatively, the wall scanner 5 can include a remotedisplay (not shown) that can be attachable to or detachable from thewall scanner 5 to provide the user with a remote display of thedetection and/or position of a stud, or the operation of the wallscanner 5. The wall scanner 5 can include a transmitter and a receiverfor communicating with the remote display. In some embodiments, theremote display is configured to display the same information as thedisplay 60.

The user can access a menu (screen 600) on the display 60 by activatingbuttons in the control section 65. From the menu, a list of optionsrelating to various settings of the wall scanner 5 is displayed on thedisplay 60. The user is able to select between English and metric unitsfor displaying the depth or location of an object (screen 605). The usercan also select whether sound is activated (screen 610). When sound isactivated, the wall scanner 5 produces, for example, a beep or a seriesof beeps to indicate the presence or depth of an object hidden behind asurface. In other embodiments, the menu is operable to controladditional functions such as display screen brightness, turning abacklight on and off, controlling the operation of a remote display, andadjusting wall scanner sensitivities. As such, the wall scanner 5 is amenu-driven device.

The display 60 also provides instructions to the user for calibratingthe wall scanner 5 after power-up. When the wall scanner 5 is operatingin the stud sensing mode, the user is prompted to place the wall scanner5 on the surface to be scanned and activate the calibration button 520(screen 615). The display 60 then indicates to the user that the wallscanner 5 is being calibrated (screen 620). The user can, if desired,manually change the sensitivity (e.g., scan depth) of the wall scanner5. For example, in one embodiment, a default depth setting of 0.5 inchesis set for the wall scanner 5 when in the stud sensing mode. To changethe scanning depth, the user activates the calibration button 520 whilethe wall scanner 5 is calibrating. Activating the calibration button 520a second time changes the scanning depth from 0.5 inches to 1.0 inches.Activating the calibration button 520 a third time changes the scanningdepth from 1.0 inches to 1.5 inches. If the calibration button isactivated a fourth time, the scanning depth cycles back to 0.5 in. Inother embodiments, the wall scanner 5 is configured with differentscanning depths and sensitivities. If an error occurs duringcalibration, the user is prompted with an error message, such as thatshown in screen 625.

After calibration, the display 60 indicates when the wall scanner 5 isscanning for a stud (screen 630). The display 60 is configured todisplay the location of a detected stud in real-time as the wall scanner5 is passing over the stud. For example, when the wall scanner 5 ismoving from left to right across a surface and a stud is detected, thestud is identified by a partially illuminated portion of the display 60(e.g., the stud is represented by a combination of illuminated pixelsand non-illuminated pixels). The illuminated pixels form a plurality oflines such as horizontal lines, vertical lines, diagonal lines, or anycombination thereof which are separated by non-illuminated pixels orlines. The display 60 also includes a visual and/or linguisticidentification of the edge of the stud (e.g., an arrow and/or the word“edge” displayed on the wall scanner display), as shown in screen 635.The display 60 can also display both edges of a stud if the width of thestud is not greater than the width of the display 60. In such aninstance, each edge is identified by an arrow and/or a linguisticidentification, and the stud is represented by a combination ofilluminated and non-illuminated portions (screen 640). The wall scanner5 includes similar visual representations of a stud's location inreal-time when the wall scanner is moving from the right to the left(screen 645).

When the wall scanner 5 is operating in the metal sensing mode, the useris prompted to hold the wall scanner 5 off of the surface to be scannedin order for the wall scanner 5 to be properly calibrated (screen 650).Similar to the stud sensing mode, the wall scanner 5 provides anindication on the display that the wall scanner 5 is being calibrated(screen 655). If an error occurs during calibration, the user isprompted with an error message, such as that shown in screen 660. Aftercalibration, the display 60 indicates when the wall scanner 5 isscanning for metal (screen 665). If the wall scanner 5 detects thepresence of metal, the user is prompted visually or audibly that metalhas been detected (screen 670). The display 60 then provides the userwith an indication of whether the detected metal is ferrous ornon-ferrous, a numerical indication of the depth of the detected object,and a visual indication of the depth of the object (screen 675). In someembodiments of the invention, the display 60 can also provide a symbolto indicate the nearest distance to a detected metal object (screen680).

A process 700 for the general operation of the wall scanner 5 isillustrated in FIG. 17. After the wall scanner 5 is powered up (step705), the default sensing mode for the wall scanner 5 is the metalsensing mode. To use the wall scanner in the metal sensing mode, theuser activates the calibration button 520 from the control section 65(step 710). If the wall scanner 5 calibrates successfully (step 715),the wall scanner 5 is ready to detect metal objects hidden behind asurface (step 720). If the wall scanner 5 does not calibrate correctly,a calibration error is displayed (step 725), and the wall scanner 5waits for a user to change sensing modes or activate the calibrationbutton 520 again (step 730). In some embodiments, if a user selects thestud sensing mode (step 735), the wall scanner 5 calibratesautomatically. In other embodiments, the user must activate thecalibration button 520. If the calibration is successful (step 740), thewall scanner 5 is ready to detect studs hidden behind a surface (step745). If the calibration is not successful, a calibration error isdisplayed (step 725), and the wall scanner 5 waits for the user tochange sensing modes or activate the calibration button 520 again (step730). Following steps 720 and 745, the wall scanner 5 also waits for theuser to change sensing modes or recalibrate the wall scanner 5 (step730). Alternatively, the user can activate the menu button 510 from thecontrol section 65 (step 750) to set up wall scanner tools (step 755)such as selecting display units and turning sound on and off. To exitthe tools setup, the user activates the menu button 510 a second time(step 760).

Thus, the invention provides, among other things, a wall scanner thatincludes a stud sensor, a metal sensor, an AC voltage sensor, a liquidcrystal display, and an easy-to-grip handle portion that allows a userto manipulate and control the wall scanner using a single hand. Thehandle portion is operable to receive a high-voltage removable andrechargeable battery pack, such as a battery pack having a lithium-basedchemistry. Various features and advantages of the invention are setforth in the following claims.

1. A wall scanner for sensing objects behind a surface, the wall scannercomprising: a housing that includes a body portion and a handle portion,the handle portion having a first axis and including a first recess,wherein the first recess is operable to receive a removable battery packalong the first axis; a first sensor of a first sensor type for sensinga first object of a first object type behind the surface; a secondsensor of a second sensor type for sensing a second object of a secondobject type behind the surface, wherein the first sensor type isdifferent than the second sensor type, and the first object type isdifferent than the second object type; a non-contact voltage sensoroperable to detect a medium carrying an alternating current behind thesurface; and a display configured to display a plurality of indicationsto a user, the indications including at least an indication of a depthof the second object behind the surface and a graphical representationof the location of the first object behind the surface.
 2. The wallscanner of claim 1, wherein the first sensor is a capacitive platesensor.
 3. The wall scanner of claim 1, wherein the second sensor is aD-coil sensor.
 4. The wall scanner of claim 1, wherein the first objecttype is a stud.
 5. The wall scanner of claim 1, wherein the secondobject type is a metal.
 6. The wall scanner of claim 1, furthercomprising a control section including a plurality of actuation devicesconfigured to be actuated by a gripping hand of a user, wherein thehandle portion is gripped by the gripping hand of the user.
 7. The wallscanner of claim 1, wherein the battery pack is a lithium-ion batterypack.
 8. A method of operating a wall scanner that includes a handleportion, a first sensor of a first type, and a second sensor of a secondtype, the method comprising: powering the wall scanner with a removablebattery pack inserted into a receiving chamber of the handle portion;sensing, using the first sensor, a first object of a first object typebehind a surface; sensing, using the second sensor, a second object of asecond object type behind the surface; wherein the first sensor type isdifferent than the second sensor type, and the first object type isdifferent than the second object type; detecting, using a non-contactvoltage sensor, a medium carrying an alternating current behind thesurface; and displaying, on a display, a plurality of indications to auser, the indications including at least an indication of a depth of thesecond object behind the surface and a graphical representation of thelocation of the first object behind the surface.
 9. The method of claim8, wherein the first sensor is a capacitive plate sensor.
 10. The methodof claim 8, wherein the second sensor is a D-coil sensor.
 11. The methodof claim 8, wherein the first object type is a stud.
 12. The method ofclaim 8, wherein the second object type is a metal.
 13. The method ofclaim 8, further comprising controlling the wall scanner using one ormore actuation devices configured to be actuated by a gripping hand of auser, wherein the handle portion is gripped by the gripping hand of theuser.
 14. The method of claim 8, wherein the battery pack is alithium-ion battery pack.
 15. A wall scanner for sensing objects behinda surface, the wall scanner comprising: a housing that includes a bodyportion and a handle portion, the handle portion forming a first axisand including a first recess, wherein the first recess is operable toreceive a battery pack having a lithium-based chemistry; a first sensorof a first sensor type for sensing a first object of a first object typebehind the surface; a second sensor of a second sensor type for sensinga second object of a second object type behind the surface, wherein thefirst sensor type is different than the second sensor type, and thefirst object type is different than the second object type; and anon-contact voltage sensor operable to detect a medium carrying analternating current behind the surface.
 16. The wall scanner of claim15, wherein the first sensor is a capacitive plate sensor.
 17. The wallscanner of claim 15, wherein the second sensor is a D-coil sensor. 18.The wall scanner of claim 15, wherein the first object type is a stud.19. The wall scanner of claim 15, wherein the second object type is ametal.
 20. The wall scanner of claim 15, further comprising a controlsection including a plurality of actuation devices configured to beactuated by a gripping hand of a user, wherein the handle portion isgripped by the gripping hand of the user.